Oceans Acidifying

By David Kattenburg

Of course, a mild mid-March in Canada’s notoriously frigid prairie capital cannot be definitively pinned on global climate change. Still, for anyone willing to listen, read and watch, the writing is on the wall. Earth is warming — and fast.

The IPCC rates degrees of confidence on a scale from ‘exceptionally unlikely’ to ‘virtually certain.’ Earth warming is “unequivocal,” it reports. Changes — including both atmospheric and ocean warming, sea level rise and reduced ice and snow cover — are “unprecedented over decades to millenia.” In the northern hemisphere, 1983-2012 was “likely the warmest 30-year period of the last 1400 hundred years.”

Ken Denman (David Kattenburg)

Cold days and nights around the planet have “very likely” dropped in number, says the IPCC, and warm days and nights have become more common.

On a less certain note, the incidence of heat waves across Europe, Asia and Australia has “likely” risen, alongside the frequency and intensity of heavy precipitation events in North America and Europe.

Moreover, it’s “virtually certain” that the number of warmer days and nights will continue to rise and the number of cold days and nights will fall.

All this warming has wreaked havoc on the Greenland and Antarctic ice sheets, and on glaciers worldwide. As expected from an energized water cycle, an increase in heavy rain and high sea-level events is “very likely.”

David Schindler (David Kattenburg)

Are humans to blame for observed changes in Earth’s climate? Most likely, says the IPCC. “It is extremely likely that human influence has been the dominant cause of the observed warming since the mid-20th century,” it says. Since the start of the industrial revolution in 1750, fossil fuel burning, cement production and deforestation have deposited an astonishing six hundred gigatonnes of carbon dioxide into the atmosphere — almost as much as the atmosphere’s carbon reservoir. No wonder concentrations of the most important greenhouse gases — carbon dioxide, methane and nitrous oxide — are higher than they’ve ever been in the past 800,000 years, and rising annually.

Danny Blair (David Kattenburg)

Predictably, the planet’s oceans are following the atmosphere in lockstep, absorbing both heat and carbon dioxide, thereby expanding and acidifying. Thirty percent of the carbon humans have released into the atmosphere has dissolved in the upper layers of the ocean, lowering ocean pH (raising acidity) by a decimal point.

A 0.1 drop in ocean pH (or 0.85 mean global temperature rise) may seem small. To put this value in perspective, the normal range of human blood pH is 7.35-7.45. A blood pH of 7.3 is considered dangerous.

So it goes on. Winnipeggers and other northerners shout hooray when T-shirt weather arrives sooner than anticipated, but global climate change poses frightening challenges. Almost two months of plus-thirty degree C days (into the nineties, for our American friends) bode poorly for human health. Among the nasty consequences of our thirst for fossil fuels: rising incidence of hitherto rare, insect-borne diseases, hundred-year floods sweeping the landscape year after year; decimated coastal landscapes.

An increasing number of informed individuals — including the climate scientists in this audio story — say it’s time for decisive action.

Andrew Weaver (David Kattenburg)

Fast Forward: Stories of Challenge & Change is produced with the generous support of the Government of Canada, the Social Justice Fund of Unifor, and the Community Radio Fund of Canada. Thanks to Roger Dumas for his wonderful human brain ‘sonifications’, one of which appears in Fast Forward intros/extros. For more information about Roger’s Pieces of Mind CD, go here.